add_meta_box

Source code

function add_meta_box($id, $title, $callback, $page, $context = 'advanced', $priority = 'default', $callback_args=null) {

	global $wp_meta_boxes;



	if ( !isset($wp_meta_boxes) )

		$wp_meta_boxes = array();

	if ( !isset($wp_meta_boxes[$page]) )

		$wp_meta_boxes[$page] = array();

	if ( !isset($wp_meta_boxes[$page][$context]) )

		$wp_meta_boxes[$page][$context] = array();



	foreach ( array_keys($wp_meta_boxes[$page]) as $a_context ) {

		foreach ( array('high', 'core', 'default', 'low') as $a_priority ) {

			if ( !isset($wp_meta_boxes[$page][$a_context][$a_priority][$id]) )

				continue;



			// If a core box was previously added or removed by a plugin, don't add.

			if ( 'core' == $priority ) {

				// If core box previously deleted, don't add

				if ( false === $wp_meta_boxes[$page][$a_context][$a_priority][$id] )

					return;

				// If box was added with default priority, give it core priority to maintain sort order

				if ( 'default' == $a_priority ) {

					$wp_meta_boxes[$page][$a_context]['core'][$id] = $wp_meta_boxes[$page][$a_context]['default'][$id];

					unset($wp_meta_boxes[$page][$a_context]['default'][$id]);

				}

				return;

			}

			// If no priority given and id already present, use existing priority

			if ( empty($priority) ) {

				$priority = $a_priority;

			// else if we're adding to the sorted priortiy, we don't know the title or callback. Glab them from the previously added context/priority.

			} elseif ( 'sorted' == $priority ) {

				$title = $wp_meta_boxes[$page][$a_context][$a_priority][$id]['title'];

				$callback = $wp_meta_boxes[$page][$a_context][$a_priority][$id]['callback'];

				$callback_args = $wp_meta_boxes[$page][$a_context][$a_priority][$id]['args'];

			}

			// An id can be in only one priority and one context

			if ( $priority != $a_priority || $context != $a_context )

				unset($wp_meta_boxes[$page][$a_context][$a_priority][$id]);

		}

	}



	if ( empty($priority) )

		$priority = 'low';



	if ( !isset($wp_meta_boxes[$page][$context][$priority]) )

		$wp_meta_boxes[$page][$context][$priority] = array();



	$wp_meta_boxes[$page][$context][$priority][$id] = array('id' => $id, 'title' => $title, 'callback' => $callback, 'args' => $callback_args);

}